Picker stick linkage



Sept. 4, 1951 G. H. HUFFERD 2,566,890

PICKER STICK LINKAGE I 2 Sheets-Sheet 1 Filed July 9, 1948 EVERY-UP p 1951 G. H. HUFFERD PICKER STICK LINKAGE 2 Sheets-Sheet 2 'Filed July 9, 1948 I 1 2177-1521-2 far I Patented Sept. 4, 1951 PICKER STICK LINKAGE George Hiram Huflerd, Shaker Heights, Ohio, assignor to Houdaille-Hershey Corporation, Detroit, Mich., a corporati Application July 9, 1948, Serial No. 37,951

11 Claims. 1

This invention relates to looms, and particularly to an improved linkage for controlling the movements of a picker stick relative to the lay of a loom.

As is well known, the movement of the picker stick of a loom is one of the most critical factors entering into the successful operation of the loom at high speeds. In all loom constructions wherein a picker is rigidly secured to the top end of the picker stick, it is essential that the path of movement of the picker along the lay follow along a substantially straight line, generally parallel to the path of movement of the shuttle. In some instances, it is desirable that the inner end portion of the path of movement of the picker be inclined slightly upwardly so as to urge the nose of the shuttle downwardly into engagement with its track at the instance that the shuttle is thrown by the picker.

As is well known, the operating characteristics and essential dimensions of any loom vary somewhat from any other loom, so that the linkage which controls the movement of the picker stick, and hence the movement of the picker, must not only produce the required linear movement of the picker but be susceptible of convenient adjustment so that the linear path of the picker movement may be optimumly located for the particular loom.

It has heretofore been suggested. that the movement of the picker stick be controlled by a linkage comprising at least two links which are pivotally connected to the picker stick, or to a supporting bracket which is rigidly secured to the picker stick. However, all such linkages heretofore proposed have required the mounting of one of the controlling links at a point adjacent the lay, or at least at a point which is relatively elevated with respect to the rock shaft. Such arrangements inherently produce difficulties in achieving the necessary operating clearance with respect to other parts of the loom, and rendered the picker stick linkage somewhat inaccessible for purposes of adjustment, repair, or replacement. Furthermore, existing linkages have not incorporated any convenient form of adiusment by which the required shifting of the path of the picker relative to the lay could be readily accomplished with a minimum shut downtime of the loom, let alone a construction that would permit adjustments to be made while the loom is operating.

Accordingly, it is an object of this invention to provide an improved picker stick linkage for looms characterized by unusual ease of manuon of Michigan facture and assemblage of its components and the improved accessibility of the linkage for adjustments, repair or replacement purposes when assembled to a loom.

A further object of this invention is to provide an improved picker stick linkage particularly adapted for use in conjunction with an hydraulic checking device for effecting the required checking of the movements of the picker stick immediately subsequent to the throwing of the shuttle and following the catching of the shuttle upon its return from the other side of the loom.

A particular object of this invention is to provide an improved picker stick linkage which will accurately control the path of movement of a picker mounted on the top end of the picker stick so as to define a substantially straight line path, and yet will permit adjustment of such path of movement of the picker so as to impart a slight upward inclination to the end of the inward stroke of the picker if such is desired.

Still another object of this invention is to provide an improved adjusting mechanism for a picker stick linkage which permits adjustment I of the eifective path of the picker without requiring disassemblage of any components from the loom.

Still another object of this invention is to provide a linkage for controlling the movements of the pickerstick of the loom characterized by the mounting of all elements of the linkage at an accessible position substantially below the lay ofthe loom and, in particular, permitting the supporting of the entire picker stick linkage by a primary bracket which may be conveniently secured to an end of the rock shaft of the loom.

The specific nature oi this invention, as well as other objects and advantages thereof, will become apparent to those skilled in the art from the following detailed description of the annexed sheets of drawings which, by way of preferred example, illustrate one specific embodiment of the invention.

On the drawings:

Figure 1 is a side elevational view of a picker stick linkage for a loom constructed in accordance with this invention;

Figure 2 is a top view of the picker stick linkage of Figure 1;

Figure 3 is a sectional view taken along the plane III-III of Figure 1;

Figure 4 is a sectional view taken along the plane IV--IV of Figure 1; and

Figure 5 is a schematic diagram illustrating the path of movement of the picker stick and 3 picker produced by a linkage embodying this invention.

As shown on the drawings:

Referring to Figure 1, the numeral I indicates a rock shaft of a loom while the numeral II indicates the conventional picker stick. Picker stick II is supported for oscillating movement with respect to the rock shaft I0, and hence with respect to the lay of the loom (not shown). by a linkage constructed in accordance with this invention which controls the movement of the picker stick so that the front face of a picker (not shown) which is conventionally secured to the top end of the stick, traverses a substantially horizontal straight line path. In general, such linkage comprises a primary bracket I2, rigidly secured to the rock shaft I0, and a secondary bracket l3 which is connected to primary bracket I2 by a pair of pivoted hnks II and I5. Links I4 and I may conveniently comprise either single or double links according to the nature of their pivotal supports, and, in the particular example shown in the drawings, link I4 constitutes two identical parallel link elements while link I5 is a single link.

Primary bracket I2 constitutes an integral casting having a split cylindrical recess I2m formed therein to receive the end of the rock shaft I 0 and being clamped to rock shaft III by a transverse bolt I2e and a transverse key I2f (Figure 3). Key I2 is disposed in a transverse aperture I29 in bracket I2 which communicates with the shaft receiving recess I2m. Key I2j is of longitudinally tapering configuration and is drawn into snug engagement with shaft ID by a nut I2h, threaded upon the threaded end portion of the key I2]. The surface of key I2! contacting shaft I0 is of concave configuration to provide a pair of parallel biting edges I27 to increase the securement of engagement of the primary bracket I2 with respect to the rock shaft I0.

In addition, primary bracket I2 defines three spaced pivot bearings I2a, I2b and He, respectively. Pivot bearing I2a is located in slightly depending relationship with respect to rock shaft Ill and provides pivotal support for one end of the link I5. Pivot hearing I 2a is preferably of bifurcated construction and thus surrounds the end of link I5. A pin I6 is provided for pivotally mounting link I5 in the bearing I2a, and that portion Iia (Figure 4) of the pin I6 which journals link I6 is eccentrically formed so that limited adjustment of the effective length of link I5 may be obtained by varying the angular position of the pivot pin I6. A nut I6b threaded upon projecting end portion I 60 of the pin I5 permits the pivot pin I6 to be clamped in any selected angular position relative to the primary bracket I2.

Pivot bearing |2b of the primary bracket I2 is also of bifurcated construction and is located directly above the end of rock shaft I0. Pivot bearing |2b provides pivotal support for the cylinder element 2| of an hydraulic check unit 20. Such check unit has a piston portion (not shown) connected to a piston rod 22 which projects out of the opposite end of the cylinder element 2|. Such check unit is constructed in any suitable manner to provide a predetermined resistance to relative movement between the piston rod 22 and the cylinder 2|, and is preferably constructed in the manner described and claimed in my copending application Serial No. 37,950, filed July 9, 1948, concurrently herewith. Reference may be had to such copending application for furthe:- description of the detailed construction of the hydraulic check unit 20.

Pivot bearing I2c of the primary bracket I2 is defined by a yoke-shaped portion |2d of primary bracket I2 and such pivot bearing is disposed in generally triangularly spaced relationship with respect to pivot bearings I20 and I2b, being located outwardly and somewhat above the end of rock shaft I0, and this pivot bearing pivotally journals one end of the links I3.

The secondary bracket I3 is of generally reversed E-shaped configuration and may be conveniently formed by a riveted assemblage of two half parts as indicated by rivets I3e. The back side of the upright portion of bracket I3 is suitably recessed as indicated at I3d so as to conform to and snugly partially surround the bottom portion of the picker stick II. Picker stick II is rigidly clamped in recess I3 by a plurality of U- shaped clamps I I which are secured to secondary bracket I3 by bolts I'Ia.

Secondary bracket I3 likewise defines three spaced pivot bearings which are respectively located in the ends of its arm portions. Thus, a bifurcated pivot bearing I3a is formed in the end of the lowermost arm portion and pivotally journals the other end of link I5. A bifurcated pivot bearing I3b is mounted in the end of the top arm portion and pivotally journals the end of the piston rod 22 of the hydraulic check unit 20. Lastly, a pivot bearing He is provided in the end of the intermediate arm of the second ary bracket I3 and pivotally journals the other ends 0f links I 4. All the pivot bearings heretofore mentioned, except pivot bearing I2a, embody conventional pivot pins and grease fittings 9.

Conventional mechanism is provided for producing the required cycling movement of the picker stick II. Thus a lug strap I8 is provided having a looped portion I8a surrounding the intermediate portion of picker stick II. Lug strap I 8 is supported and horizontally oscillated by an actuating link I9 which is cam driven in timed relationship to the movements of the loom and rock shaft III in accordance with well known procedure.

The top end of the picker stick II has a conventional picker element (not shown) secured thereto. As will be understood by those skilled in the art, periodically the lug strap- I8 shifts the picker stick I I from its extreme outward position to its extreme inward position, and in so doing, accelerates the picker stick I| so rapidly that the shuttle (not shown) which is in contact with the picker on the upper end of the picker stick II, will be violently thrown to the other side of the loom. After the shuttle is thrown, the inward movement of the picker stick II is checked by the hydraulic unit 20 and the picker stick is brought to rest. Thereupon, a torsion spring 40 operating between secondary bracket I3 and link I5 is effective to urge the picker stick II outwardly to at least an intermediate neutral position, such as illustrated in Figure 1 wherein a spring stop 4| carried by an arm l2 pivotally secured at 43 to secondary bracket I 3, engages a fixed pin 44 transversely mounted in link I5. At this point, the picker stick II is preferably positioned so that the picker will be contacted by the shuttle when the shuttle is thrown back from the other side of the loom.

The construction of the leaf spring stop 4| is described in detail and claimed in my copending aseasoo application, Serial No. 37,952, now Patent No. 2,512,897, filed concurrently herewith, and reference should be had thereto for a more detailed description of such element.

Upon contact of the returning shuttle with the picker on the top end of the picker stick II, the stick II is violently driven outwardly, and such outward movement is checked by the hydraulic unit 20 to rapidly and smoothly bring the picker stick H to rest without producing a rebounding of the shuttle therefrom or permitting excessive forces to be developed in the picker stick II or any portion of its control linkage.

As is well known, it is most essential for proper loom operation that the picker mounted on the top end of the picker stick follow a substantially straight line path which is generally parallel to the path of movement of the shuttle. Through proper proportioning of the length of the links I4 and IS, the picker stick linkage heretofore described will control movements of the picker stick II in such manner that the shuttle contacting portions of a picker mounted on its top end will traverse such a substantially straight line path. This is clearly illustrated by the schematic diagram of Figure 5. In Figure 5 the short line P at the top of the picker stick at right angles thereto is a schematic representation of a picker element secured thereto. The solid heavy lines in Figure 5 indicate the position of the picker stick and its control linkage in a neutral or intermediate position, the dash lines indicate the extreme outward position of the picker stick and its control linkage, and the dotdash lines indicate the extreme inward position of the picker stick and its control linkage. It will be observed that the frontedge of the picker element P traverses a substantially straight line path indicated by the numeral 23.

In the event that it is desired to effect an adjustment of the location of the straight line path of the picker relative to the lay of the loom, then angular adjustment of the eccentric pin 16 will vary the effective length of the link l5 and such variation will result in a shifting of the straight line path of the picker. In this manner, the path of the picker may be modified to produce a slightly rising inclination at the extreme inner end of its stroke at the point where the shuttle departs from the picker and thus impart a downward bias on the nose of the shuttle tending to maintain it in its track.

It is not'possible to generally predict the proper dimensions of the links I4 and I5 as well as the spacing between the respective supporting pivot bearings l2a, l3a and Hi), I31), so as to permit the determination of suitable proportions for any length and angular swing of the picker stick utilized on any particular loom. However, it should be noted that a linkage constructed in accordance with this invention is entirely supported by the rock shaft i0 through the primary bracket 12. By the complete elimination of any support of the picker stick from the lay of the loom, the height of the lay relative to the rock shaft becomes a relatively inconsequential factor in the design of the picker stick linkage. Heretofore, other types of linkages which employed at least one link mounted on the lay were subjected to unpredictable variations due to substantial differences in the relative displacement of the lay from the rock shaft of any particular loom. Furthermore, the described linkage, being located at the base of the loom adjacent the rock shaft,

a is entirely accessible for adjustment, repair or replacement purposes. The adjustment of the effective length of link I! through angular adjustment of the pivot pin I6 can be accomplished so rapidly that the loom will be shut down for a minimum time.

It should be further noted that the described picker stick linkage may be applied to any existing loom without modification of the remaining components.

It will, of course, be understood that various details of construction may be modified through a wide range without departing from the principles of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

I claim as my invention:

1. In a loom having a lay, a rock shaft supporting the lay and a flying shuttle traversing the lay, the improvements comprising a primary bracket mounted on one end of said rock shaft, a secondary bracket, a picker stick secured to said secondary bracket, said picker stick having the top portion thereof disposed adjacent the lay in the path of the shuttle, a picker mounted on said top portion of the picker stick, and a pair of spaced links pivotally connected between said brackets, thereby controlling the path of movement of said picker stick relative to said lay. said links being constructed and'arranged to move said picker along a substantially straight line path, and a check unit having relatively movable elements, one of said elements being pivotally secured to said primary bracket and the other of said elements being pivotally secured to said secondary bracket.

2. In a loom having a rock shaft, a picker stick control linkage comprising a primary bracket secured to the rock shaft, said primary bracket having a plurality of spaced pivot bearings formed thereon, a secondary bracket secured to the picker stick, said secondary bracket also having a plurality of spaced pivot bearings formed thereon, a pair of links connected between said primary and secondary brackets, each of said links having one end portion pivotally journaled in one pivot bearing of said primary bracket and the other portion journaled in one pivot bearing of said secondary bracket, whereby the path of movement of said picker stick relative to the loom is controlled and hydraulic means between said primary bracket and said secondary bracket to check rapid relative motion between said brackets.

3. In a loom having a rock shaft and a picker stick, a picker stick control linkage comprising a primary bracket secured to the rock shaft, said primary bracket having at least three spaced pivot bearings formed thereon, a secondary bracket secured to the picker stick, said secondary bracket having at least three spaced pivot bearings formed thereon, a first link having its ends respectively pivoted to one pivot bearing of said primary bracket and one pivot bearing of said secondary bracket, 8. second link having its ends respectively pivoted to a second pivot bearing of said primary bracket and a second pivot bearing of said secondary bracket, an hydraulic check unit having relatively movable piston and cylinder elements, one of said elements being pivotally secured to the third pivot bearing of said primary bracket and the other of said elements being pivotally secured to the third pivot bearing of said secondary bracket, whereby the 7 path of movement of said picker stick relative tothe loom is controlled and fluid resistance to such movement is provided by said hydraulic check unit.

4. The combination defined in claim 3 plus means for adjusting the eflective length or one of said links, thereby permitting adjustment of the path of movement of the picker relative to the loom.

.5. The combination defined in claim 3 wherein said primary bracket has an integrally formed split sleeve portion constructed to surround said rock shaft, and means for clamping said split sleeve portion into rigid engagement with said rock shaft. a

6. In a loom having a rock shaft, a picker stick control linkage comprising a primary bracket secured to the rock shaft and having a plurality of spaced pivot bearings formed thereon, a secondary bracket secured to the picker stick and having a plurality of spaced pivot bearings formed thereon, link means connected between said primary and secondary bracket, each of said link means having one end portion pivotally journaled in a pivot bearing on said primary bracket and the other portion journaled in a pivot bearing of said secondary bracket, whereby the path of movement of said picker stick relative to the loom is controlled and hydraulic means between said primary bracket and said secondary bracket to check rapid relative motion between said brackets, said primary bracket further defining an integrally formed split sleeve portion constructed to surround said rock shaft, said loom having means for clamping said split sleeve portion into rigid engagement with said rock shaft.

7. In a picker stick linkage for looms, a rock shaft, a support bracket thereon, a mounting bracket adapted for connection to the picker stick, a link pivotally connecting said mounting bracket to said support bracket, eccentric pivot means for securing said link to one of said brackets for adjustment of the eiiective length of said link, and hydraulic check means between said support bracket and said mounting bracket to check rapid relative movement therebetween.

8. In a picker stick linkage for looms, a rock shaft, a support bracket thereon, a mounting bracket adapted for connection to the picker stick, a linkage pivotally connecting said mounting bracket and said support bracket and hydraulic check means between said support bracket and said mounting bracket to check rapid relative movement therebetween.

9. In a picker stick linkage for looms of the type having a rock shaft, a support bracket connected to said rock shaft, a mounting bracket adapted for connection to the picker stick, a plurality of links connecting said mounting bracket and said support bracket, hydraulic check means between said support bracket and said mounting bracket to check rapid relative movement therebetween and a spring stop operative between said support bracket and said mounting bracket to retain the picker stick in an intermediate shuttle catching position beingl-yieldable utndfr. the impact of the shuttle with the picker s 1c 10. In a picker stick linkage for looms of the type having a rock shaft, a shuttle, and a picker stick, a connecting bracket supported on said rock shaft, a mounting bracket adapted for connection to the picker stick, a plurality of links pivotally connecting said connecting bracket and I said mounting bracket, hydraulic check means between said connecting bracket and said mounting bracket to check rapid relative movement therebetween, means operative between said connecting bracket and said mounting bracket to normally bias the picker stick to an outward position, and a stop element operative between said connecting bracket and said mounting bracket 7 to normally retain the picker stick in an intermediate shuttle-catching position against said bias and being yieldable to. the impact of the shuttle with the picker stick.

11. In a picker stick linkage for looms, a rock shaft, 2, support bracket thereon, a mounting bracket adapted for connection to the picker stick, a link pivotally connecting said mounting bracket in said support bracket, eccentric pivot means for securing said link to one of said brackets for adjustment of the effective length of said link, and hydraulic check means between said support bracket andsaid mounting bracket to check rapid relative movement therebetween. said support bracket defining an integrally formed split sleeve portion constructed to surround said rock shaft for clamp engagement GEORGE HIRAM HUFFERD.

REFERENCES CITED The following references are of record in the flie of this patent:

UNITED STATES PATENTS therewith.

Number Name Date 571,729 Paige Nov. 17, 1896 1,255,725 Finch Feb, 5, 1918 2,433,764 Kotteman Dec. 30, 1947 2,483,517 Balogh Oct. 4, 1949 FOREIGN PATENTS Number Country Date 383,901 Great Britain Nov. 24, 1932 862,988 France Dec. 23, 1940 

